This invention relates generally to wellbore casings, and in particular to wellbore casings that are formed using tubing having threaded portions.
Conventional tubing used to form wellbore casings includes internally threaded portions at one end and externally threaded portions at another end. The internal threaded portions can be damaged during handling.
The present invention is directed to overcoming one or more of the limitations of the existing procedures for forming wellbores.
According to one aspect of the present invention, a device for protecting an end portion of a tubular member having an internally threaded portion is provided that includes a locking member having an externally threaded portion adapted to threadably mate with the internally threaded portion of the tubular member, and a collar adapted to mate with the locking member and an end portion of the tubular member.
According to another aspect of the present invention, a method of protecting an end portion of a tubular member having an internally threaded portion is provided that includes supporting the internally threaded portion of the tubular member and supporting the exterior of the end portion of the tubular member.
According to another aspect of the present invention, a method of protecting the end portions of a plurality of tubular members having internally threaded portions is provided that includes coupling a locking member to the internally threaded portions of the tubular members and coupling a collar to the end portions of the tubular members and the locking members. The wall thicknesses of the collars vary as a function of the wall thicknesses of the end portions of the tubular members.